Module One, Lecture Seven

Question 1

What is Photosynthesis ?

Answer 1

Synthesis using light which is responsible for almost all the planet’s energy resources. It is the conversion of light energy into chemical energy

Question 2

Describe the structure and function of the Chloroplasts…

Answer 2

It is the site of photosynthesis. It has three membranes ( Outer, Inner and Thylakoid ). Three compartments ( Intermembrane space, Stroma, Thylakoid Space )

Question 3

Where do Light Reactions take place?

Answer 3

Thylakoid Membrane

Question 4

Where does Carbon Fixation occur?

Answer 4

Stroma

Question 5

What is the importance of Photosynthesis? ( 3 )

Answer 5

1. Food Source
2. Oxygen Production
3. Carbon Dioxide Absorption

Question 6

What are the two stages of Photosynthesis?

Answer 6

1. Light-Dependent Reactions
2. Calvin Cycle ( Light-Independent Reactions )

Question 7

Describe the Light-Dependent Reactions of Photosynthesis… ( 4 )

Answer 7

1. Chlorophyll, found in the thylakoid membrane absorbs light energy
2. Light energy is used to split water molecules, releasing Oxygen, Electrons, and Hydrogen Ions
3. Electrons from water are passed along an electron transport chain, releasing energy that is used to pump hydrogen ions across the thylakoid membrane
4. The energy released by the electron transport chain is used to generate ATP and NADPH, which are energy-carrying molecules

Question 8

Describe the Calvin Cycle ( Light-Independent Reactions )…

Answer 8

1. Carbon from the atmosphere is combined with a five-carbon molecule, forming a six-carbon compound
2. The six-carbon compound is converted into a three-carbon compound, using the energy from ATP and NADPH
3. The three-carbon compound is then used to regenerate RuBP ( single carbon molecule ), allowing the cycle to continue
4. Some of the three-carbon compounds are converted into glucose, a type of sugar which can be stored for later use